docs: def get_fields(self):
          """
          Convert default field names for this sub-serializer into versions where
          the field name has the prefix removed, but each field object knows the
          real model field name by setting the field's `source` attribute.
          """
          prefix = getattr(self.Meta, 'source_prefix', '')
          fields = super(ModelSubSerializer, self).get_fields()
          fields_without_prefix = OrderedDict()
          for field_name, field in fields.items():
              if field_name.startswith(prefix):
                  # Set real model field name as field's `source` unless the
                  # source is already explicitly set, in which case it is
                  # probably a method name not the direct field name
                  if not field.source:
                      field.source = field_name
                  field_name = field_name[len(prefix):]
              fields_without_prefix[field_name] = field
          return fields_without_prefix